The German patent 11 57 789 discloses a method for the synthesis of organosilicon compounds which contain the group ##STR2## (M=any divalent, optionally halogenated hydrocarbon group). The distinguishing feature of the synthesis involves reacting compounds carrying the .tbd.Si--M--O--X group (X=hydrogen or an acyl group) with sulfuric acid, sulfur trioxide, chlorosulfonic acid or amidosulfonic acid at temperatures up to 180.degree. C. and the reaction products are optionally equilibrated and/or hydrolyzed. As starting organosilicon compound, organopolysiloxanes of the general formula EQU [R.sub.n SiO.sub.2-1/2n ].sub.x [R.sub.n Si(MOH).sub.m O.sub.2-1/2(n+m) ].sub.y EQU [R.sub.n Si(MOCOR).sub.m O.sub.2-1/2(n+m) ].sub.z
are used, wherein M is as defined above and R represents any, optionally halogenated hydrocarbon group or hydrogen, n and m have a value of 0 to 3 and x, y and z can assume any value.
In the specification and examples, the linear groups --C.sub.3 H.sub.6 --, --C.sub.3 H.sub.5 Cl-- and C.sub.4 H.sub.8 -- are explicitly used as the M group. The compounds can be converted into their salts, particularly into their ammonium salts. They are suitable for impregnating textiles, leather, glass, wood or masonry and can be used as emulsifiers or as substances with detergent properties.
The German Offenlegungsschrift 15 95 775 discloses sulfate group-containing organosilicon compounds of the general formula ##STR3## in which M is sodium or potassium, R is an alkyl group with 1 to 3 carbon atoms, R' is a univalent hydrocarbon group with more than 7 carbon atoms and free of aliphatic unsaturations, R" is the same as R' or hydrogen, "a" is a number from 3 to 8, x is zero or a number from 1 to 10 and y is zero or a number from 1 to 150. These compounds are comparable to those of the German Patent 11 57 789. In the German patent 11 57 789, methods are described for the synthesis of organopolysiloxanes which have lateral sulfatoalkyl groups. On the other hand, the compounds described in the German Offenlegungsschrift 15 95 775 are analogous compounds which have the sulfatoalkyl groups in the .alpha., .omega. position.
Surprisingly, it has now been found that the salts of the corresponding hexyl sulfate esters combine outstanding surfactant properties with above average resistance to hydrolysis. This behavior could not have been anticipated by extrapolating the properties of the next lower or next higher homologous alkyl sulfate ester and is therefore surprising to those skilled in the art.